/*--------------------------------------------------------
 * Copyright © 2009 – 2010* France Telecom
 * This software is distributed under the "Simplified BSD license",
 * the text of which is available at http://www.winktoolkit.org/licence.txt
 * or see the "license.txt" file for more details.
 *--------------------------------------------------------*/

/**
 * Implement a semitransparent layer 
 * 
 * @methods:
 *	--> show: display the layer
 *	--> hide: hide the layer
 *	--> refresh: update the display (in case of a change of height in the page for instance)
 *	--> update: update the color, opacity and zIndex of the layer. Use this method if you want to change the opacity or color or zIndex after you called the 'show' method.
 *
 * @attributes:
 * 	--> visible: true if the Layer is displayed, false otherwise
 * 	--> color: the hexa code of the layer color (default value: #000)
 * 	--> opacity: opacity level of the layer (default value: 0.3)
 * 	--> zIndex: the hierarchical level of the layer (default value: 998)
 *
 * @compatibility:
 * 	--> Iphone OS2, Iphone OS3, Iphone OS4, Android 1.1, Android 1.5, Android 2.1, Android 2.2, Android 2.3, BlackBerry 6, Bada 1.0
 * 
 * @author:
 * 	--> Jerome GIRAUD
 */

(function(wink) {
	
var applyStyle = wink.fx.apply;
var _container = null;
var _sublayer = null;
var _added = false;
	
wink.ui.xy.layer =
{
	visible: false,
	color: '#000',
	opacity: 0.3,
	zIndex: 998,
	
	/**
	 * Display the layer
	 */
	show: function()
	{
		if (!_added) 
		{
			this._initDom();
		}
		
		_container.onclick = function()
		{
			var onclick = wink.ui.xy.layer.onclick;
			if ( wink.isSet(onclick) )
			{
				onclick();
			}
		};
		
		if (!this.visible)
		{
			applyStyle(_sublayer, {
				height: document.body.scrollHeight + 'px'
			});
			applyStyle(_container, {
				display: 'block'
			});
			this.visible = true;
		}
	},
	
	/**
	 * Hide the layer
	 */
	hide: function()
	{
		if (_added && this.visible) 
		{
			applyStyle(_container, {
				display: 'none'
			});
			this.visible = false;
		}
	},
	
	/**
	 * Update the display
	 */
	refresh: function()
	{
		if (_added && this.visible) {
			applyStyle(_sublayer, {
				height: document.body.scrollHeight + 'px'
			});
		}
	},
	
	/**
	 * Update the color and opacity of the layer
	 */
	update: function()
	{
		if (!_added) 
		{
			this._initDom();
		}

		applyStyle(_container, {
			"z-index": this.zIndex
		});
		applyStyle(_sublayer, {
			backgroundColor: this.color,
			opacity: this.opacity
		});
	},
	
	/**
	 * Create the layer
	 */
	_initDom: function()
	{
		var doc = document;
		_container = doc.createElement('div');
		applyStyle(_container, {
			position: 'absolute',
			display: 'none',
			top: 0,
			width: '100%',
			"z-index": this.zIndex,
			"tap-highlight-color": 'rgba(0, 0, 0, 0)'
		});

		_sublayer = doc.createElement('div');
		applyStyle(_sublayer, {
			width: '100%',
			backgroundColor: this.color,
			opacity: this.opacity
		});

		_container.appendChild(_sublayer);
		doc.body.appendChild(_container);
		
		_added = true;
	}
};

//Bindings
wink.layer = wink.ui.xy.layer;

})(wink);